CN112736999A - Series battery equalization device with multiple flyback converters - Google Patents
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J7/00—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
- H02J7/0013—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries acting upon several batteries simultaneously or sequentially
- H02J7/0014—Circuits for equalisation of charge between batteries
- H02J7/0019—Circuits for equalisation of charge between batteries using switched or multiplexed charge circuits
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M10/00—Secondary cells; Manufacture thereof
- H01M10/42—Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells
- H01M10/4207—Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells for several batteries or cells simultaneously or sequentially
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M10/00—Secondary cells; Manufacture thereof
- H01M10/42—Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells
- H01M10/425—Structural combination with electronic components, e.g. electronic circuits integrated to the outside of the casing
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M10/00—Secondary cells; Manufacture thereof
- H01M10/42—Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells
- H01M10/425—Structural combination with electronic components, e.g. electronic circuits integrated to the outside of the casing
- H01M10/4257—Smart batteries, e.g. electronic circuits inside the housing of the cells or batteries
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M10/00—Secondary cells; Manufacture thereof
- H01M10/42—Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells
- H01M10/44—Methods for charging or discharging
- H01M10/441—Methods for charging or discharging for several batteries or cells simultaneously or sequentially
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J7/00—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
- H02J7/0013—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries acting upon several batteries simultaneously or sequentially
- H02J7/0014—Circuits for equalisation of charge between batteries
- H02J7/0016—Circuits for equalisation of charge between batteries using shunting, discharge or bypass circuits
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M10/00—Secondary cells; Manufacture thereof
- H01M10/42—Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells
- H01M10/425—Structural combination with electronic components, e.g. electronic circuits integrated to the outside of the casing
- H01M2010/4271—Battery management systems including electronic circuits, e.g. control of current or voltage to keep battery in healthy state, cell balancing
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/10—Energy storage using batteries
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- Power Engineering (AREA)
- Charge And Discharge Circuits For Batteries Or The Like (AREA)
Abstract
The invention relates to the field of battery equalization of series-connected single batteries, in particular to a series-connected battery equalization device with a plurality of flyback converters, which comprises n battery packs, 4n relays, n flyback converters and 1 controller, wherein the battery packs are connected in series. Two ends of each single battery are respectively connected with the primary side of the corresponding flyback converter through a relay, the secondary side of the flyback converter is connected with the anode and the cathode of the next battery pack, and the secondary side of the last flyback converter is connected with the anode and the cathode of the first battery pack; the controller compares the SOC value of the single battery with the average value of the SOC of all the single batteries, and the single batteries are charged or discharged through the flyback converter so as to realize the balance of the SOC of the single batteries. The invention uses the flyback converter to control the equalizing direction and speed, can conveniently control the direction and the magnitude of the input/output current of the flyback converter according to the acquired voltage data of the single battery and calculate the SOC thereof according to the voltage data, and further control the equalizing direction and the speed.
Description
Technical Field
The invention relates to the field of battery equalization of series-connected single batteries, in particular to a series-connected battery equalization device with a plurality of flyback converters.
Background
To meet the requirements of energy storage configurations, rechargeable batteries have been widely adopted in various fields such as renewable energy storage systems, electric vehicles, and telecommunications industries. Since the terminal voltage of a cell is low, in most applications, it is often necessary to connect a plurality of cells in series to form a battery module to achieve a desired voltage level.
However, imbalance between the respective unit cells in the battery module is a common phenomenon, such as a difference in terminal voltage, state of charge (SOC), and the like between the cells. This imbalance is caused by both intrinsic and extrinsic condition differences between the cells. Inherent differences are often limited by the manufacturing process and can only be minimized by optimizing the manufacturing and screening processes. The external operating condition differences include temperature differences and external auxiliary circuit differences. Non-uniform temperature distribution in the battery module may affect battery characteristics and cause performance variation, and higher operating temperature may increase capacity and power but may accelerate aging of the unit cells. Lower operating temperatures can reduce performance. External auxiliary circuits are used to detect, control and protect the cells, but these circuits consume different power from each cell, exacerbating the imbalance between cells.
The largest effect of battery imbalance is energy loss in the battery module. Generally, the battery with the lowest and highest end SOC will limit the performance of the entire battery module. A highly reliable, efficient Battery Management System (BMS) is critical for applications powered by rechargeable batteries, and cell balancing is one of the most important functions of a BMS. Cell balancing techniques help to distribute energy evenly among the cells. Without cell balancing, some of the capacity or energy in the battery module would be wasted, especially for long strings of series connected battery modules operating under frequent charge and discharge conditions.
In order to maintain the balance of the single batteries in the battery module, a plurality of balancing circuits, devices and methods have been proposed. At present, the circuits, devices and methods can be generally classified into three types, the first type is to make the overall parameters close to the single battery with lower SOC by releasing the energy of the single battery with higher SOC, the second type is to transfer the energy from the single battery with higher SOC to the single battery with lower SOC, and the third type is to control the charging and discharging process to ensure the balance between the batteries.
For the series-connected battery modules, the charging and discharging currents of all the batteries are equal, so the third type of equalization scheme is not suitable for the series-connected battery modules. The energy of the single battery with higher SOC released in the first solution is usually dissipated in energy dissipation elements such as resistors, which makes the whole device extremely inefficient. Combining the above discussion, the second category is a solution that is generally considered superior.
However, the existing equalizing device and method belonging to the second solution cannot always give consideration to the cost and the equalizing speed of the device. For example, the scheme of adding a set of equalization circuit to each single battery can achieve the fastest equalization speed, but the corresponding device cost will rise, and the complexity and reliability of the device will rise. However, a simple shared equalization circuit is often difficult to implement fast equalization, which is no longer applicable in a scenario with a high requirement on equalization speed.
Disclosure of Invention
In order to solve the above problems, the present invention provides a series battery equalization apparatus having a plurality of flyback converters.
The series battery balancing device with the flyback converters comprises n battery packs connected in series, 4n relays, n flyback converters used for charging and discharging and 1 controller used for controlling the relays and the flyback converters, wherein n is a positive integer greater than or equal to 3;
the battery pack comprises 2 single batteries connected in series;
the two ends of each single battery are respectively connected with the primary side of the corresponding flyback converter through the controllable switches, the secondary side of each flyback converter is connected with the anode and the cathode of the next battery pack, and the secondary side of the last flyback converter is connected with the anode and the cathode of the first battery pack;
the controller compares the SOC value of the single battery with the average value of the SOC of all the single batteries, controls the corresponding relay to connect the single battery needing to be balanced to the primary side of the flyback converter, and then charges or discharges the single battery through the flyback converter so as to realize the balance of the SOC of the single batteries.
Preferably, the relay includes a positive relay and a negative relay, a first contact of the positive relay is connected to the positive electrode of the single battery, a second contact of the positive relay is connected to the primary side of the flyback converter, a first contact of the negative relay is connected to the negative electrode of the single battery, and a second contact of the negative relay is connected to the primary side of the flyback converter.
Preferably, the positive relay and the negative relay both belong to a normally open electromagnetic relay.
The controller compares the SOC value of the single battery with the average value of the SOC of all the single batteries, controls the corresponding relay to connect the single battery needing to be balanced into the primary side of the flyback converter, and then charges or discharges the single battery through the flyback converter so as to realize the balance of the SOC, and the method comprises the following steps:
and if the SOC value of the single battery is higher than the SOC average value, controlling the corresponding flyback converter to discharge the single battery, and transferring the redundant electric quantity to the next pair of batteries so as to enable the SOC value of the single battery to be equal to the SOC average value.
The controller compares the SOC value of the single battery with the average value of the SOC of all the single batteries, controls the corresponding relay to connect the single battery needing to be balanced into the primary side of the flyback converter, and then charges or discharges the single battery through the flyback converter so as to realize the balance of the SOC, and the method comprises the following steps:
and if the SOC value of the single battery is lower than the SOC average value, controlling the corresponding flyback converter to charge the single battery, and supplementing missing charges by taking the next pair of batteries as charge sources so as to enable the SOC value of the single battery to be equal to the SOC average value.
Compared with the prior art, the invention has the beneficial effects that:
(1) two adjacent single batteries can share one flyback converter, so that the cost and the complexity of the device are reduced, and the reliability of the device is improved;
(2) the invention uses the flyback converter to control the equalizing direction and speed, can conveniently control the direction and the magnitude of the input/output current of the flyback converter according to the acquired voltage data of the single battery and calculate the SOC thereof according to the voltage data, and further control the equalizing direction and speed;
(3) the secondary side of the flyback converter is only bridged at two ends of a pair of series batteries, and the voltage stress of the controllable power switch at the secondary side is low.
Drawings
The present invention will be described in further detail with reference to the accompanying drawings and specific embodiments.
FIG. 1 is a schematic diagram of a conventional switched capacitor cell equalization circuit;
FIG. 2 is a schematic diagram of a conventional single cell equalization circuit based on a multi-flyback converter;
fig. 3 is a schematic diagram of a series battery equalization apparatus having a plurality of flyback converters according to the present invention;
fig. 4 is a specific example schematic diagram of a series battery equalization apparatus having multiple flyback converters according to the present invention, which has 6 cells;
fig. 5a is a state 1 schematic diagram of a series cell balancing apparatus of the present invention with multiple flyback converters;
fig. 5b is a state 2 schematic of the series cell balancing apparatus of the present invention with multiple flyback converters;
fig. 5c is a state 3 schematic of a series cell balancing apparatus of the present invention with multiple flyback converters;
FIG. 5d is a state 4 schematic of the series cell balancing apparatus of the present invention with multiple flyback converters;
fig. 6 is a waveform diagram of typical electrical signals of a series cell equalization apparatus having multiple flyback converters.
Detailed Description
The technical solutions of the present invention will be further described below with reference to the accompanying drawings, but the present invention is not limited to these embodiments.
The traditional battery equalization circuit cannot give consideration to both the device cost and the equalization speed. As shown in fig. 1, the conventional switched capacitor type single cell equalizing circuit has the characteristics of simplicity and reliability, but has the disadvantage that the equalizing speed is unstable and uncontrollable, and as shown in fig. 2, the conventional single cell equalizing circuit based on multiple flyback converters overcomes the disadvantage that the equalizing speed is uncontrollable, but each single cell needs to be provided with one flyback converter, so that the overall cost and reliability of the device are greatly reduced. In view of this, the present application provides a series battery balancing apparatus with a plurality of flyback converters, which considers both the apparatus cost and the balancing speed, and at the same time, can use a controllable switching device with smaller stress.
The invention provides a series battery balancing device with a plurality of flyback converters, which comprises a series battery balancing device with a plurality of flyback converters, and comprises n battery packs connected in series, 4n relays, n flyback converters used for charging and discharging and 1 controller used for controlling the relays and the flyback converters, wherein n is a positive integer more than or equal to 3; the battery pack comprises two single batteries connected in series; the two ends of each single battery are respectively connected with the primary side of the corresponding flyback converter through a relay, the secondary side of each flyback converter is connected with the anode and the cathode of the next battery pack, and the secondary side of the last flyback converter is connected with the anode and the cathode of the first battery pack; the controller compares the SOC value of the single battery with the average value of the SOC of all the single batteries, controls the corresponding relay to connect the single battery needing to be balanced to the primary side of the flyback converter, and then charges or discharges the single battery through the flyback converter so as to realize the balance of the SOC of the single batteries.
The relay comprises an anode relay and a cathode relay, wherein a first contact of the anode relay is connected with the anode of the single battery, a second contact of the anode relay is connected with the primary side of the flyback converter, a first contact of the cathode relay is connected with the cathode of the single battery, and a second contact of the cathode relay is connected with the primary side of the flyback converter. The positive relay and the negative relay both belong to normally open electromagnetic relays.
The flyback converters belong to bidirectional direct current-direct current converters, each converter consists of 1 transformer and 2 controllable power switches, the non-homonymous end of the primary side of the transformer is connected with the drain electrode (collector electrode) of one controllable power switch to form the primary side of the converter, the homonymous end of the secondary side of the transformer is connected with the drain electrode (collector electrode) of the other controllable power switch to form the secondary side of the converter, the non-homonymous end of the transformer at the secondary side of the converter is connected with the anode of the first battery in the next pair of batteries, and the source electrode (emitter electrode) of the controllable power switch at the secondary side of the converter is connected with the cathode of the second battery in the next pair of batteries.
And if the SOC value of the single battery is higher than the SOC average value, controlling the corresponding flyback converter to discharge the single battery, and transferring the redundant electric quantity to the next pair of batteries so as to enable the SOC value of the single battery to be equal to the SOC average value.
And if the SOC value of the single battery is lower than the SOC average value, controlling the corresponding flyback converter to charge the single battery, and supplementing missing charges by taking the next pair of batteries as charge sources so as to enable the SOC value of the single battery to be equal to the SOC average value.
In an exemplary embodiment of the present invention, as shown in fig. 3, a series battery equalization apparatus having a plurality of flyback converters is provided. In order to simplify the description of the core functions of the device, taking n to 3, as shown in fig. 4, there is provided an equalizing device with 3 flyback converters and 6 series-connected single cells, the equalizing device is composed of 6 single cells, 6 positive relays, 6 negative relays, and 3 flyback converters, and each flyback converter includes 1 transformer and 2 controllable power switches.
The 6 single batteries are balanced objects of the battery balancing device and form a battery pack in a series connection mode; the 6 positive pole relays all belong to normally open type electromagnetic relays, one end of an output loop of each positive pole relay is connected with the positive poles of the 6 single batteries connected in series, and the other ends of the output loops are connected in pairs according to the serial number sequence (a first positive pole relay is connected with a second positive pole relay, a third positive pole relay is connected with a fourth positive pole relay, and a fifth positive pole relay is connected with a sixth positive pole relay), and then are respectively connected with the same-name ends of the primary sides of the 3 transformers, and the positive pole relays are controlled by a battery positive pole selection signal sent by a controller.
The 6 negative pole relays all belong to normally open type electromagnetic relays, one end of an output loop of each negative pole relay is connected with the negative poles of the 6 serially connected single batteries, the other end of the output loop is connected in pairs according to the serial number sequence (a first negative pole relay is connected with a second negative pole relay, a third negative pole relay is connected with a fourth negative pole relay, a fifth negative pole relay is connected with a sixth negative pole relay), and then the negative pole relays are respectively connected with the source electrodes (emitting electrodes) of the 3 primary side controllable power switches of the flyback converters, and the negative pole relays are controlled by battery negative pole selection signals sent by the controller.
The 3 flyback converters belong to bidirectional DC-DC converters, each converter consists of 1 transformer and 2 controllable power switches, the non-homonymous end of the primary side of the transformer is connected with the drain (collector) of one controllable power switch to form the primary side of the converter, the homonymous end of the secondary side of the transformer is connected with the drain (collector) of the other controllable power switch to form the secondary side of the converter, the non-homonymous end of the transformer on the secondary side of the converter is connected with the positive pole of the first battery in the next pair of batteries (the non-homonymous end of the secondary side of the first transformer is connected with the positive pole of the first battery, namely the third battery, the non-homonymous end of the secondary side of the second transformer is connected with the positive pole of the first battery, namely the fifth battery, and the non-homonymous end of the secondary side of the third transformer is connected with the first battery in the first pair of batteries, i.e. the positive pole of the first cell), the source (emitter) of the converter secondary side controllable power switch is connected to the negative pole of the second cell of the next pair of cells (the source of the first converter secondary side controllable power switch is connected to the negative pole of the second cell of the second pair of cells, i.e. the fourth cell, the source of the second converter secondary side controllable power switch is connected to the negative pole of the second cell of the third pair of cells, i.e. the sixth cell, the source of the third converter secondary side controllable power switch is connected to the negative pole of the second cell of the first pair of cells, i.e. the second cell).
Next, the modal analysis of the device is performed by taking as an example that the SOC of the cell B1 is high and the SOC of the cell B2 is low.
Collecting all single battery voltages Vi(i is 1,2,3,4,5,6), and calculates the respective SOCsiAnd its average value SOCaveThen, if the SOC of the single battery B11If the voltage is higher than the preset value, an action command is sent to the positive relay K1+ and the negative relay K1-, and the moment corresponds to the time t0 in the figure 6;
t 0-t 1: the time delay is carried out to ensure that the relays K1+ and K1-are stably closed, and no current passes through the primary side and the secondary side of the transformer T1 in the interval;
t 1-t 2: at time t1, the controllable power switch S1a on the primary side of the flyback converter is turned on, and then, as shown in fig. 5a, the primary side of the transformer receives the voltage V1The exciting current starts to rise, and the rising rate is constant, as follows:
dim/dt＝V1/Lm
wherein imFor transformersMagnetic current, LmThe transformer is used as excitation inductance. In this interval, the flyback converter secondary side current is always 0.
t 2-t 3: at time t2, the current on the primary side of the flyback converter rises to the set current threshold, the controllable power switch S1a on the primary side is controlled to turn off, then, as shown in fig. 5b, the anti-parallel diode of the controllable power switch S1b on the secondary side of the converter conducts the follow current, the exciting current drops, and the dropping rate is constant, as follows:
dim/dt＝-(V1+V2)/Lm
the primary side current of the flyback converter is always 0 in the interval.
t 3-t 4: at time t3, the current on the secondary side of the flyback converter drops to 0, and the anti-parallel diode of the secondary side controllable power switch S1b stops freewheeling and turns off when receiving the back voltage. In the interval, no current passes through the primary side and the secondary side of the transformer T1;
t 4-t 5: in the interval, the circuit mode repeats t 1-t 2;
t 5-t 6: in the interval, the circuit mode repeats t 2-t 3;
t 6-t 7: SOC of battery cell B1 at time t61＝SOCaveAnd when the condition that the balancing process is ended is reached, the controllable power switch is not controlled to be switched on or switched off, and at the time of t7, the action commands of the positive relay K1+ and the negative relay K1-are cancelled.
Collecting all single battery voltages Vi(i is 1,2,3,4,5,6), and calculates the respective SOCsiAnd its average value SOCaveThen, if the SOC of the single battery B22If the current is lower than the preset value, an action command is sent to the positive relay K2+ and the negative relay K2-, and the time corresponds to the time t0 in the figure 6;
t 0-t 1: the time delay is carried out to ensure that the relays K2+ and K2-are stably closed, and no current passes through the primary side and the secondary side of the transformer T1 in the interval;
t 1-t 2: at time t1, the controllable power switch S1b on the secondary side of the flyback converter is turned on, and then the secondary side of the transformer is subjected to voltage (V) as shown in FIG. 5c1+V2) The exciting current starts to rise and risesThe rate is constant as follows:
dim/dt＝(V1+V2)/Lm
in this interval, the flyback converter primary side current is always 0.
t 2-t 3: at time t2, the current on the secondary side of the flyback converter rises to the set current threshold, the controllable power switch S1b on the secondary side is controlled to turn off, then, as shown in fig. 5d, the anti-parallel diode of the controllable power switch S1a on the primary side of the converter conducts the follow current, the exciting current starts to fall, and the falling rate is constant, as follows:
dim/dt＝-V2/Lm
the current on the secondary side of the flyback converter is always 0 in the interval.
t 3-t 4: at time t3, the current on the primary side of the flyback converter drops to 0, and the anti-parallel diode of the primary side controllable power switch S1b stops freewheeling and turns off when receiving the reverse voltage. In the interval, no current passes through the primary side and the secondary side of the transformer T1;
t 4-t 5: in the interval, the circuit mode repeats t 1-t 2;
t 5-t 6: in the interval, the circuit mode repeats t 2-t 3;
t 6-t 7: SOC of battery cell B2 at time t62＝SOCaveAnd when the condition that the balancing process is ended is reached, the controllable power switch is not controlled to be switched on or switched off, and at the time of t7, the action commands of the positive relay K2+ and the negative relay K2-are cancelled.
The embodiment of the invention provides a series battery balancing device with a plurality of flyback converters, which uses the flyback converters to balance unbalanced batteries in a series battery pack and can flexibly configure the magnitude of balanced current, the transfer direction of balanced charge and a balance judgment standard; in addition, the device gives consideration to the cost and the balancing speed of the device, and realizes the active balancing of all the single batteries by using the least controllable power switch on the premise of not sacrificing the balancing speed; the device is also significantly better in reliability than conventional solutions due to the smaller number of controllable power switches used.
Various modifications or additions may be made to the described embodiments or alternatives may be employed by those skilled in the art without departing from the spirit or ambit of the invention as defined in the appended claims.
Claims (5)
1. The series battery balancing device with the flyback converters is characterized by comprising n battery packs connected in series, 4n relays, n flyback converters used for charging and discharging and a controller used for controlling a controllable switch, wherein n is a positive integer larger than or equal to 3;
the battery pack comprises two single batteries connected in series;
the two ends of each single battery are respectively connected with the primary side of the corresponding flyback converter through a relay, the secondary side of each flyback converter is connected with the anode and the cathode of the next battery pack, and the secondary side of the last flyback converter is connected with the anode and the cathode of the first battery pack;
the controller compares the SOC value of the single battery with the average value of the SOC of all the single batteries, controls the corresponding relay to connect the single battery needing to be balanced to the primary side of the flyback converter, and then charges or discharges the single battery through the flyback converter so as to realize the balance of the SOC of the single batteries.
2. The series battery balancer with multiple flyback converters as claimed in claim 1, wherein the relay includes a positive relay and a negative relay, the first contact of the positive relay is connected to the positive pole of the single battery, the second contact is connected to the primary side of the flyback converter, the first contact of the negative relay is connected to the negative pole of the single battery, and the second contact is connected to the primary side of the flyback converter.
3. The series battery equalization apparatus with multiple flyback converters of claim 2, wherein the positive relay and the negative relay are both normally-open electromagnetic relays.
4. The apparatus for equalizing a series of batteries with a plurality of flyback converters of claim 1, wherein the controller compares the SOC value of a single battery with the average SOC of all single batteries, controls a corresponding relay to connect the single battery to be equalized to the primary side of the flyback converter, and then charges or discharges the single battery through the flyback converter to realize the SOC equalization, comprising:
and if the SOC value of the single battery is higher than the SOC average value, controlling the corresponding flyback converter to discharge the single battery, and transferring the redundant electric quantity to the next pair of battery packs so as to enable the SOC value of the single battery to be equal to the SOC average value.
5. The apparatus for equalizing a series of batteries with a plurality of flyback converters of claim 1, wherein the controller compares the SOC value of a single battery with the average SOC of all single batteries, controls a corresponding relay to connect the single battery to be equalized to the primary side of the flyback converter, and then charges or discharges the single battery through the flyback converter to realize the SOC equalization, comprising:
and if the SOC value of the single battery is lower than the SOC average value, controlling the corresponding flyback converter to charge the single battery, and supplementing missing charges by taking the next pair of batteries as charge sources so as to enable the SOC value of the single battery to be equal to the SOC average value.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202011370515.2A CN112736999A (en) | 2020-11-30 | 2020-11-30 | Series battery equalization device with multiple flyback converters |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202011370515.2A CN112736999A (en) | 2020-11-30 | 2020-11-30 | Series battery equalization device with multiple flyback converters |
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| CN202011370515.2A Pending CN112736999A (en) | 2020-11-30 | 2020-11-30 | Series battery equalization device with multiple flyback converters |
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